Transmission operating mechanism



Dec, 18, 1956 E. R. PRICE 2,774,251

TRANSMISSION OPERATING MECHANISM Original Filed June 3. 1949 2Sheets-Sheet l Wgk ATTOENE Y Dec. 18, 1956 E. R. PRICE 2777492531TRANSMISSION OPERATING MECHANISM Original Filed June 3. 1949 2Sheets-Sheet 2 h INTOR.

RICE

ATTOEN E. Y

2,774,251 Patented Dec. 18, 1956 fiice TRANSMISSION OPERATING MECHANISMEarl R. Price, South Bend, Ind., assignor to Bendix AviationCorporation, South Eend, Ind, a corporation of Delaware Originalapplication June 3, 1949, Serial No. 97,011, now

Patent No. 2,695,983, dated November 30, 1954. Divided and thisapplication September 16, 1954, Serial No. 456,430

Claims. (Cl. 74-365) This invention relates to power actuated mechanismsfor selectively moving a control element to one or the other of twooperative positions, and more particularly to gear shifting mechanismsfor operating the speed changing gearing commonly used in coupling theengine or prime mover with the driving wheels or the like of anautomotive vehicle or the propeller of a marine craft.

One of the objects of my invention is to provide a power shiftingmechanism for motor vehicle change speed mechanism that is electricallyselective under the control of the driver.

A further object of the invention is to provide a compact, easilyserviced and relatively simple double acting power unit well adapted foruse in mechanism for operating the shiftable elements of the two speedaxle structure of an automotive vehicle.

Yet another object of my invention is to provide an electric motor foroperating a selective gear type of transmission to alternately establishthe same in first one or the other of two gear ratio settings, saidmotor being controlled by a manually operable selector switch and twoout off switches; and the power element of the motor being connected tothe transmission by means including torsion spring means.

The above and other objects and features of the invention will appearmore fully hereinafter from a consideration of the following descriptiontaken in connection with the accompanying drawings where one embodimentof the invention is illustrated by way of example.

Figure 1 is a diagrammatic view of an automotive vehicle embodying thetransmission operating mechanism of my invention;

Figure 2 is a sectional view disclosing details of a preferredembodiment of my invention;

Figure 3 is a sectional view, taken on the line 3-3 of Figure 2disclosing details of the mechanism of the latter figure;

Figure 4 is another view of the mechanism of Figure 2 disclosing themotor operated cut out switch of the electrical control means of Figures1 and 5; and

Figure 5 is a diagrammatic view disclosing the electrical hook-up of theelectrical mechanism of my invention.

The transmission operating power means constituting my invention ispreferably employed to operate a two speed axle transmission mechanismof an automotive vehicle; however, it may be employed to operate anypower transmitting mechanism of the power plant of a land or marinevehicle wherein said mechanism is selectively movable to two operativepositions.

Referring to Figure l a transmission operating power unit It} isdetachably mounted on the carrier of what is known in the automotive artas a two speed axle, that is a part of the driving mechanism of thevehicle effecting a gear ratio in addition to the usual driving ratioand different therefrom. This two speed axle mechanism, actuated by theshifter mechanism of my invention, is indicated by the reference numeral12 and a change speed transmission mechanism cooperating therewith isindicated by the reference numeral 14. The transmission operatingmechanism constituting my invention may be employed to operate a Maybachclutch type of two speed axle, however, any other well known two speedaxle construction is equally well operated by the mechanism of myinvention.

There is disclosed, in Figures 2 to 4 inclusive, a preferred embodimentof the aforementioned power unit 10 of the transmission operatingmechanism of Figure 1, said unit constituting the principle feature ofmy invention. Describing this unit a casing 16 is provided with apartition 18; and this partition, together with end plates 20 and 22 andthe wall of the casing, outline two compartments 24 and 26. Thecompartment 26 houses a worm gear 28 mounted upon and secured, by a pin30, to a switch operating shaft 32 journalled at one end in a hubportion 34 of the partition 18, and at its other end in a hub portion 36of the end plate 20. The worm gear 23 is driven by a worm 38, Figure 3,drivably mounted upon a shaft 40; and the latter is journalled, at itsupper and lower ends, in portions of the casing 16. The shaft 40 isdrivably connected to the shaft of a double field reversible electricmotor 42 of any well known design.

As is disclosed in Figures 1 and 5 the motor 42, which is grounded, maybe controlled by electrical means including a manually operated singlepole double throw selector switch 44 conveniently mounted on the controlpanel 46 within the drivers compartment of the vehicle. The movablecontact of the switch 44 may be electrically connected to a groundedbattery 48; and fixed contacts 56 and 52 of said switch are electricallyconnected, respectively, to a motor operated out out switch 54 and amotor operated cut out switch 56, all as is disclosed in Figure 5. Theswitch 54 preferably includes a fixed contact 58 mounted upon a plate 66secured to the motor casing and electrically connected, by a conductor62, to one of the field windings of the motor 42 disclosed in Figure 3.The switch 54 also includes a movable contact 64 pivotally mounted upona post 65, Figure 4, to which there is secured the upper end of a clip61 the lower end of which is secured to but insulated from a side wallof the motor casing. A clip 63 likewise secured to the casing, and aconductor 67, Figure 1 connected to the clip complete the electricalconnections between the movable contact 64 of the switch 54 and thecontact 59 of selector switch 44, the contact 64, post 65, and clipbeing of electrically conductive material.

The switch 56, being a duplicate of the switch 54, is not described indetail herein. Suffice it to say that a movable contact 66 of the switch56 is electrically connected, by means including a conductor 69, Figure1, to the contact 52 of the selector switch 44; and a fixed con tact 71of the switch 56 is electrically connected, by means including aconductor 68, to the other field winding of the motor 42. Completing thedescription of the switches 54 and 56, springs and 72, Figure 4, securedto a post 74 of electrical insulating material, serve, respectively, tobias the movable contacts 64 and 66 to their switch closed positions.The means for opening the switches 54 and 56 include a cam 76 ofelectrical insulating material, secured to a reduced end portion of theshaft 32, Figure 2; and as will be apparent from an inspection of Figure4 the cut-out operation of the switches 54 and 56 is effected by anangular movement of the cam.

Describing now the yieldable transmission operating force transmittingmeans of the power unit 10 a disk shaped crank 77, rotatably mounted ona sleeve member 78 mounted on the shaft 32, is pivotally connected by acrank pin 80 to a connecting rod 82. As is disclosed in 3 Figure 3 thisrod is, at one of its ends, bent around the shaft 32 and is pivotallyconnected, at its other end, to a hollow rod .84 which is in turnadapted to be connected to the shifter fork of the two speed axlemechanism of Figure 1. As is disclosed in Figure 3 the latter rod isslidably mounted in a portion of the casing 16; and the rod 84 and therod 82 connected thereto, together constitute a part of the motor unit.As is disclosed in Figure 2, to the crank 77 and worm gear 28 there aresecured, respectively, pins 86 and 88. A preloaded torsion spring 99,sleeved over a hub portion of the worm gear and over the sleeve 78, isconnected at one of its ends to the pin 86 and at its other end to thepin 38. Stop means, including pins 92 and 94 mounted on the worm gear28, and a stop 96 mounted in the motor casing, serve to limit theloading of the torsion spring 99 and to control the operation of the cutoff switch mechanism.

Briefly describing the operation of the transmission operating unit ofFigures 1 to 4 inclusive a closure of the above described selectorswitch prior to a release of the accelerator results in an energizationof the motor 42; and the latter operation results in a rotation of theworm gear 23 to wind up the spring 90. Then when the driver releases theaccelerator the driving torque is reversed and the spring 90 expandsthereby effecting a transmission operating movement of the rod 82 in oneor the other of its two directions of movement depending of course onthe particular operation of the transmission selected by the driver.

There is thus provided, by the transmission operating unit 10 togetherwith the controls therefor, an effective and efiicient transmissionoperating mechanism well adapted to operate either a two speed axle ofan automotive vehicle or other change speed transmission of the powerplant of the vehicle. The motor unit 10 constituting the essence of myinvention, includes relatively few moving arts comprising a worm andworm gear driven by a double field reversible electric motor said motorbeing connected to the transmission by yieldable force transmittingmeans including a crank and pin mechanism and a spring member. With theunit 10 the timed cutting out of operation of the electric motor, by theoperation of the cut off switches, serves, in cooperation with theoperation of the stop mechanism, to insure the desired inertia operationof the moving parts to effect a maximum compression of the torsionspring; and with said unit the operation of the yieldable forcetransmitting means positioned between the worm and worm gear mechanismand the transmission, insures a relatively quiet operation of thetransmission.

This application is a division of my application No. 97,011 filed June3, 1949 said application having matured into U. S. Patent No. 2,695,983dated November 30, 1954.

Although only one embodiment of the invention has been illustrated anddescribed, various changes in the form and relative arrangements of theparts may be made to suit requirements.

I claim:

1. A power mechanism adapted to operate a change speed transmission ofan automotive vehicle, said mechanism including an electric motor havinga shaft, a casing, means within the casing comprising a worm gear andworm driving unit drivably connectedto said shaft, a transmissionoperating rod, force transmitting means interconnecting the rod and wormgear including a disk directly connected to the rod and furtherincluding a spring interposed between the disk and the worm gear of saidunit, said spring being energized when the motor is l energized toeffect an operation of the unit; out OK switch mechanism for in partcontrolling the operation of the motor, and means connected to the wormgear for 0pcrating the switch mechanism.

2. A power unit adaptable to operate a change speed transmission of anautomotive vehicle including a casing, a reversible electric motorhoused within a portion of the casing, said motor comprising a driveshaft, a worm gear and worm driving mechanism drivably connected to saidshaft, a transmission operating rod mounted in the casing, forcetransmitting means interconnecting the rod and worm gear including adisk mounted parallel with the worm gear and further including a springwhich is energized when the motor is energized to effect an operation ofthe unit, cut off switch mechanism for in part controlling the operationof the motor, means connected to the worm gear for operating the switchmechanism, and stop means, including a part mounted on the worm gear forlimiting the movement thereof, after the switch mechanism has operatedto de-energize the motor.

3. A power unit adaptable to operate a two speed axle transmission of anautomotive vehicle including, in combination, a double field reversibleelectric motor, a worm and worm gear mechanism connected to the driveshaft of the motor, a transmission operating rod, a double acting forcetransmitting means interconnecting the rod and worm gear including aspring connected to the worm gear said spring being compressed when themotor is energized and further including a disk interconnecting thespring and rod, a motor operated cut off switch mechanism for in partcontrolling the operation of the motor, and means connected to the wormgear for operating the switch mechanism.

4. A power unit adaptable to operate a two speed axle transmission. ofan automotive vehicle including a double field reversible electricmotor, a worm and worm gear unit connected to the drive shaft of themotor, a transmission operating rod, double acting force transmittingmeans interconnecting the rod and worm gear including a torsion springwhich is compressed when the motor is energized, said spring beingdirectly connected to the gear of the Worm and worm gear unit, a motorcut off switch mechanism for in part controlling the operation of themotor, means connected to the worm gear for operating the switchmechanism, and stop means for limiting the spring compressive movementof the worm gear, said stop means coming into play after the cut offswitch means is operative to de-energize the motor.

5. A preassembled unit for use in the transmission operating mechanismof an automotive vehicle comprising a casing, a motor housed within thecasing, a worm and worm gear unit housed within the casing the wormbeing drivably connected to the drive shaft of the motor, a transmissionoperating rod slidably mounted in the casing, and force transmittingmeans interconnecting the rod and worm gear including a crank and pinmechanism, a torsion spring interconnecting the crank of the lattermechanism with the worm gear, and a rod interconnecting the pin of thecrank and pin mechanism with the transmission operating rod.

References Cited in the file of this patent UNITED STATES PATENTS2,462,779 Russell Feb. 22, 1949 2,589,643 Thomas et al Mar. 18, 19522,599,724 Russell June 10, 1952 2,610,518 Goedeke et al. Sept. 16, 19522,695,983 Price Nov. 30, 1954

